Energy Cost Analysis of Incorporating Air Intake Cooling System in Omotosho Phase 1 Thermal Power Plant

The gas turbine power plants in Nigeria are sited in locations where the standard ambient air temperature condition of 150 C rarely occurs. This off – rated temperature condition brings about a low thermal performance of the power plants. One method that can be used to improve the thermal performance of gas turbine power plants is to reduce the temperature of air entering them by using combustion turbine air – inlet cooling technology. This paper presents the energy cost analysis of incorporating air – intake cooling system in Omotosho Phase I Thermal Power Station. Data obtained from the power station were used for the economic analysis. The analysis indicates that four hundred and ninety eight million, one hundred and thirty eight thousand, seven hundred naira and sixty kobo only as profit. Thus retrofitting the existing gas turbine power plant with air – intake cooling system is economically viable. It also provides a better system performance and is an attractive investment opportunity. Keywords: Energy, cooling, ambient air temperature, cost analysis, profit, efficiency, power output

Development and characterization of a quaternary nitrate based molten salt heat transfer fluid for concentrated solar power plant

Over the past few years, there has been growing interest in using inorganic quaternary nitrate-based molten salt mixtures as a highly effective heat transfer fluid (HTF) for concentrated power plants, primarily because they can achieve low melting temperatures. However, the high viscosity of these salt mixtures is still a significant challenge that hinders their widespread adoption. The high viscosity leads to high pumping power requirements, which increases operational costs, and reduces the efficiency of the Rankine cycle. To address this challenge, this study developed and characterized a novel quaternary molten salt, focusing on the effect of LiNO3 additions on the salt's viscosity, thermal conductivity, melting point temperature, heat capacity, and thermal stability. The quaternary mixture comprised KNO3, LiNO3, Ca(NO3)2, and NaNO2, with varying percentages of each salt. The study utilized various standard techniques to examine the characteristics of the developed mixture. Results showed that increasing LiNO3 content led to a decrease in melting temperature, higher heat capacity, improved thermal stability, conductivity, and reduced viscosity at solidification temperature. The lowest endothermic peak for the new mixture emerged at 73.5 °C, which is significantly lower than that of commercial Hitec and Hitec XL, indicating better potential for use as a heat transfer fluid for concentrated solar thermal power plant applications. Furthermore, the thermal stability results showed high stability up to 590 °C for all the samples examined. Overall, the new quaternary molten salt shows promise as a potential replacement for current organic synthetic oil, offering a more efficient solution